Between the stars' absolute magnitudes<span> or </span>luminosities<span> versus their </span>stellar classifications<span> or </span>effective temperatures<span>. </span>
<em><u>Hertzsprung-Russel diagram or HR diagram is a scatter plot or a graphical tool that is used by astronomers to classify stars based on their luminosity, color, temperature, spectral type and also the stage of evolution.</u></em>
<em><u>The HR diagram plots the temperature of the stars against the luminosity, or the color of starts against absolute magnitude.</u></em>
The HR diagram is divided into stages, for example those stars at the stable phase of hydrogen burning are found within the main sequence according to their mass.
